This invention relates to a nuclear power plant including a reactor combination building in which a condensate storage tank is accommodated.
Generally, in a nuclear power plant, particularly including a BWR (Boiling Water Reactor), a condensate storage tank is installed for storing excess condensate and water as an emergency water source of a reactor coolant injection system or a low or high pressure coolant injection system for suppressing superheat in a reactor core in case of loss of coolant accident. In a known type nuclear power plant, the condensate storage tank building is located as an independent structure separated from a reactor building in the same site of the power plant and the tank building is connected through a conduit laid above or under the ground surface.
The independent location of the condensate storage tank building apart from the reactor building hinders effective utilization of the site of the nuclear power plant. The condensate storage tank building includes a shielding made of concrete which surrounds the condensate storage tank with a certain space therebetween for preventing leakage of radiation of the condensate stored in the tank. Further, a flashing board or equipment is provided for the tank for preventing rain water from entering into a portion, i.e. the space desbribed above, where the leakage of the condensate from the tank is detected. The provision of the concrete shielding and flashing equipment complicates and enlarge the condensate storage tank building.
In addition, since the condensate storage building is installed independently of the reactor building and directly exposed to wind, rain, snow, or the like, the maintenance and inspection must be carried out frequently. Since the nuclear power plant is often installed at an area near a sea shore, consideration of salt injury is necessary. In a case when the nuclear power plant is installed in an area subject to cold weather, heating means for the condensate storage tank is additionally required.
Moreover, in many cases, a nuclear power plant installation area does not satisfy desired conditions of civil engineerings and since the reactor building and a condensate storage building are independently installed on a hard rock bed at a depth of about 40-50 m under the ground surface, troublesome excavating works are required.